The present invention relates to the field of attachments for skid steerloaders and other power loaders having lift arms. In particular, it relates to an attachment for a skid steer loader especially adapted for lifting and placing loads at an extended distance from the loader.
Landscaping involves the movement and manipulation of a variety of materials, most of which are heavy. Examples of one-piece items include plants with rootballs, boulders, stone blocks, concrete pavers and timbers. Flowable or granular materials such as earth, gravel, crushed stone, and sand also must be dug, or scooped, located and spread. Much of landscaping activity takes place in confined areas which are bounded by structures, fences, plantings or trees. Traditionally, therefore, these materials have been manipulated primarily by hand labor. Shovels, wheelbarrows and handcarts are often employed.
Versatile skid steer loaders have allowed landscapers to move many of these materials with less muscular effort, but loaders too have limitations. The standard bucket of a skid steer loader is about the same width as the machine or greater, typically from four to eight feet. Standard buckets can be readily used to move granular materials but tend to dump the materials in a pile as wide as the bucket. Often, it is necessary to fill wheelbarrows with flowable granular products for delivery to especially confined areas. A standard bucket is exceptionally poorly adapted for this task since it is much wider than the wheelbarrow. Thus, laborious hand shoveling is employed to fill wheelbarrows.
U.S. Pat. No. 4,068,771 to Zimmerman and U.S. Pat. No. 5,692,875 to Boman disclose devices that attach narrow chute-like assemblies to standard width loader buckets. These devices are necessarily limited in their reach by the ability of the loader to counterbalance the weight of the load. Additionally, the attachment of these devices seriously limits the utility of the loader bucket for other tasks and mostly precludes the handling of unit items as discussed below. In the case of Zimmerman, when the chute-like attachment is in place, the bucket can not be used for other purposes until the attachment is entirely removed. Boman includes a hydraulic chute swing mechanism but the chute remains above the bucket interfering with the carrying of items of any significant height.
A skid steer loader with a bucket may be employed to move plants, blocks, boulders, timbers and the like but individual items must often be manhandled into and out of the bucket. Substantial manual labor must be employed if the items are to be unloaded from a truck or trailer. A loader equipped with fork tines like those of a forklift may advantageously be used for such items. Depending on the design, however, these fork tines either make the bucket of the machine unusable until removed, or require the removal of the bucket for installation. In either case, valuable time and effort is expended in changing equipment.
Landscaping also requires the digging of holes and trenches for plantings, footings and the like. A skid steer tractor with a bucket can dig holes, but the hole is of necessity at least as wide as the bucket. Backhoe attachments capable of trenching are available but require considerable time to install and remove and severely limit maneuverability of the tractor when attached. Backhoe attachments are also expensive, complex, bulky and difficult to transport. Lastly, they must be removed before any other attachment can be employed.
Additionally, landscapers often mix small quantities of concrete by hand for setting fence posts and the like. It would be convenient to be able to raise the concrete mixing trough to a comfortable level and transport small portions of the heavy mix to the location of placement mechanically rather than by hand labor.
The landscaping industry would benefit greatly from an implement which could be used to handle and move both granular and unit materials, and deposit the materials at an extended distance from the loader. This implement should be simple, inexpensive, easily transported, and be inherently stable, even while carrying loads at an extended distance from the base of the loader. The use of this implement would significantly reduce the need for hand shoveling and laborious manipulation of heavy items commonly used in landscaping.
The invention hereof comprises a unique bucket attachment and sub-attachments adaptable for use with skid steer loaders and other small earth moving equipment. The bucket attachment has a much smaller ratio of width to length than conventional loader buckets. It also provides for a much longer reach than conventional loader implements. The bucket attachment is well adapted for use with a skid steer loader or tractor for trenching, excavation and moving of granular materials such as earth, sand, gravel or crushed rock. The bucket attachment can include a fork having short tines at the extreme end. In addition to increasing the reach of the attachment, the fork assists in the manipulation of heavy unit items such as balled and burlapped trees and shrubs, boulders, and blocks of stone or concrete.
The bucket attachment hereof successfully accommodates a number of competing design factors. Tractors such as skid steer loaders employ counterweights to balance the loads lifted by the lift arms. The moment arm of the counter weight is particularly limited by the need to keep the wheelbase of the loader short in order to facilitate steering in tight quarters. Without taking into consideration such factors, it would be possible to increase the reach of the bucket attachment to a point where the equipment was inherently unstable, or that it could no longer lift any significant load. Load characteristics also need to be accommodated. Unit objects typically are dense and compact but relatively small. Therefore, they do not limit the reach of the bucket attachment as much as do granular materials. A typical concrete retaining wall block weighs eighty to one hundred pounds. A large balled and burlapped tree or shrub may weight three hundred pounds. Crushed landscape stone weighs about 110 pounds per cubic foot. It can be seen that in order to carry a significant load of dense granular material safely it is desirable to keep the load as close to the front of the loader as possible. This is one reason why all loader buckets known to the applicant are configured with a ratio of width to length of about 2.5:1 or greater.
In order to keep the load of granular material as near to the front of the loader as possible, the bucket attachment hereof is beneficially shaped in a wedge shaped profile. In addition, there is a limit to the travel of the portion of the lift arm assembly that controls the pitch of the bucket relative to the tractor. It is desirable that heavy loads be carried close to the tractor and as low as possible. If it is desired to move the load to the rear of the elongate bucket it is preferred to join the attachment plate to the floor of the bucket at an acute angle. This allows the operator to tilt the bucket nose up to shift flowable, granular materials to the rear of the bucket.
In order to assure that the bucket attachment can be safely used it is helpful that the bucket attachment be self-limiting in load capacity. That is accomplished by limiting the width of the bucket itself. A ratio of width to length of about 0.30 to 0.38 is preferred. This also reduces the weight of the bucket, leaving more load capacity available. Additionally, the wedge shaped profile concentrates the weight of the attachment near to the tractor.
The fork assembly provides for ease of manipulation of blocks, boulders and the like. The fork tines are short and preferably limited to two and, unlike backhoe or excavator teeth, they are beveled upward so that the sharpest end is at the top. The fork assembly is preferably formed of one integral piece. This increases dexterity of manipulation and provides the added benefit of facilitating the spreading and grading of granular materials.
The bucket attachment hereof comprises an upright frame adapted for removable attachment to the lift arms of an earthmoving vehicle. This frame is integrated into the back plate of the bucket. The bottom plate and side plates are preferably formed of a single metal plate and are secured to the back plate forming an elongate bucket with approximately vertical sides, which is substantially constant in width from front to rear. Fork tines are attached to the front of the bucket assembly. The side plates of the bucket assembly may incorporate collars to receive a locking pin or pins that may be utilized to secure sub-attachments to the bucket attachment.
Sub-attachments may include a smaller mini-bucket which further extends the length and reach of the assembly. The mini-bucket may be attached to extend beyond the end of the fork and it can be especially advantageous if the capacity of the mini-bucket is about equal to that of a six cubic foot construction wheelbarrow. This allows the safe and easy filling of such wheelbarrows without laborious hand shoveling. The smaller size of the mini-bucket also provides a self limiting load feature so that the counterbalance of the tractor is not exceeded.
The mini-bucket may be secured to the bucket attachment by a simple pin passed through apertures on the bucket and the mini-bucket. Further, the mini-bucket may include hook assemblies that cause the apertures on the mini-bucket to align with the apertures on the bucket attachment to facilitate insertion of the locking pin. The hook assemblies also serve to transmit digging force from the bucket attachment to the mini-bucket and to hold down the front end of the mini-bucket relative to the bucket attachment.
A liner made of a durable nonstick material such as polyethylene may be incorporated into the bucket to facilitate the hand mixing of small quantities of concrete. The liner may be held in place by spring clips or other appropriate means to prevent it from inadvertently sliding out of the bucket during concrete pouring operations.
The size and weight of the bucket attachment allow it to fit readily into the rear of a pickup truck or van for transport. It is also small enough to be placed transversely on many trailers.
Sub-attachments can be constructed in a simple and economical manner since they do not require a large and expensive attachment plate to secure them to the bucket attachment. Sub-attachments may secure to the bucket attachment by being bolted in place of the fork assembly or by being held in place by a pin in a manner similar to the mini-bucket. Sub-attachments may include a bolt on chute in a straight or funnel shaped configuration, an extended digging bar, an extended length scraper adapted for pushing or pulling materials and a granular material chute held in place by a pin in a manner similar to the mini-bucket.